The present project will evaluate through a Randomized Controlled Trial (RCT) with 5-month follow-up, the efficacy (5-month time horizon), adjunctive to TAU, of three 8-week interventions: a) the Mindfulness for Health program (i. e., M4H), b) a Cognitive Training (CT) program through NeuronUp platform and a program combining both (Mindfulness and Cognitive Training program, i. e., UP4H), a, as compared to TAU, in children (7-12 years old) with ADHD. In order to evaluate stability of clinical changes and to determine the mechanisms of action of the interventions studied, pre-post changes and at 5-months followup after the start of treatment will be evaluated in ADHD symptoms (inattention, hyperactivity, impulsivity), general functioning, clinical global impression, executive functions (verbal fluency, working memory, cognitive flexibility, inhibition), and comorbid symptoms (disruptive behavior, anxiety and depression) along with mindfulness skills. In the field of personalized treatment in ADHD, the design of the present study will also make it possible to establish whether certain baseline psychosocial and clinical characteristics may be associated with short- and medium-term clinical response to each of the treatments studied.

Introduction: The NeuroMind study is aimed at assessing the efficacy of 3 interventions based on Mindfulness and/or Cognitive Training programs: a Mindfulness and Cognitive Training program (i. e., UP4H), a Mindfulness program (i. e., M4H) and a Cognitive Training program (i. e. CT). This study will evaluate the short- and mid-time efficacy of these 3 interventions for the first time in children with ADHD. The objectives of this 5-month RCT, are (i) to examine the efficacy of adding UP4H, M4H or CT to treatment-as-usual (TAU) for children (7-12 years old) with ADHD; (ii) to identify pre-post differences in ADHD symptoms (inattention, hyperactivity, impulsivity), in executive functions (verbal fluency, working memory, cognitive flexibility, inhibition), and in comorbid symptoms (disruptive behavior, anxiety and depression) in the four study arms and (iii) to analyze the role of the mindful attention awareness as a psychological process variable mediator of 5-month clinical outcomes. Methods and analysis: Participants will be 120 children with ADHD (7-12 years old) recruited at CSMIJ Sant Joan de Déu Terres de Lleida (Lleida, Spain), randomly allocated to one of the four study arms: TAU vs TAU+CT vs TAU+M4H vs TAU+UP4H. A comprehensive assessment to collect ADHD symptoms (inattention, hyperactivity, impulsivity), executive functions (verbal fluency, working memory, cognitive flexibility, inhibition), comorbid symptoms (disruptive behavior, anxiety and depression), mindful attention awareness, general functioning and clinical global impression will be conducted pre-intervention, post-intervention (8 weeks), and at 5-month follow-up. Linear mixed-effects model analyses, mediation analysis and sensitivity analyses will be conducted on the basis of intention-to-treat approach and according to whether the patients are completers, or whether they completed the majority of the sessions (75% attendance).

Inclusion Criteria:

• Children of both sexes, between 7 and 12 years of age.
• Diagnosis of ADHD according to the DSM-5 criteria by a specialist and confirmed by the Kiddie-Schedule for Affective Disorders and Schizophrenia, Present and Lifetime Version (K-SADS-PL).
• ADHD medication dose is stable in the last 2 months or there is an informed decision on not taking ADHD medication.
• Children and parents have an adequate mastery of the Spanish language.
• Children and parents are available to meet all visits.
• Children's representatives (either parents or legal guardians) must understand the conditions of the study and sign the informed consent.
• Psychiatric comorbidities are allowed except psychosis, bipolar illness, active suicidality, untreated posttraumatic stress disorder or substance use (checked by the structured interview K-SADS-PL) , provided ADHD is the primary diagnosis in the child.
• Children have an IQ ≥ 80 checked by the Kaufman Brief Intelligence Test (K-BIT).

Exclusion Criteria:

• Diagnosis of Autism Spectrum Disorder (ASD) according to the DSM-5 criteria by a specialist or confirmed by the Social Communication Questionnaire (SCQ).
• Children who received psychological or psycho-educational treatment in the last 2 months or whose parents don't agree not to seek it during the study.
• Children have participated in a mindfulness programme in the past or the current year
• Children are participating in another clinical trial.